Barrel: 16" Chrome-lined, chrome moly vanadium. Chambered in 5.56 NATO, with a 1/7 twist, M4 barrel extension, and a carbine-length gas system. The M4 profile barrel is high pressure tested and magnetic particle inspected and then phosphate coated. Barrel is finished off with an .750" diameter F-marked front sight base with sling swivel, standard handguards and an A2 flash hider. Barrel is made for us right here in SC by FN Manufacturing.